http:www'flickr'comphotos21218849N033901372331sizesl

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PaperPrototyping
http//www.flickr.com/photos/21218849_at_N03/39013723
31/sizes/l/
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A word from our sponsor (EECS)

• Want a permanent job, an internship, or info
  about grad school?
• Want free (?) food?
• http//eecs.oregonstate.edu/
  
• undergraduate/seniorDinner/index.ht
  m
• Seniors get first dibs, juniors get unclaimed
  spots

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Customers and users should be your friends

• They probably know much more about the problem
  than you do.
• They probably have some ideas about how to solve
  the problem.
• They are your best resource for discovering your
  own mistakes before you start to code.

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Risk an unwanted event that has negative
consequences

• Risk impact the loss that would result if a risk
  turns into a problem
• Measured in time, quality, cost
• Risk likelihood probability that the risk will
  turn into a problem
• Risk exposure impact likelihood
• Risk control the degree to which you can reduce
  exposure

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Risk management

• Risk management
• Risk assessment
• Risk identification
• Risk analysis
• Risk prioritization
• Risk control
• Risk reduction
• Risk management planning
• Risk resolution

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Example risksin an e-commerce application

• Risk mobile phones (unexpectedly) need to be
  supported
• Impact 30 of revenue? Likelihood ???
• Risk credit card validation component cannot
  handle debit cards
• Impact 10 of revenue? Likelihood ???

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Risk management and prototyping

• Traditional requirements-gathering
• Good for controlling risks regarding what the
  system should do
• But dont know what the system should look like
• Prototyping
• Good for controlling risks regarding what the
  system should look like
• Not so good for non-visual aspects of the system

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Top ten risks

• Personnel shortfalls
• Unrealistic schedules and budgets
• Developing the wrong software functions
• Developing the wrong user interface
• Gold plating
• Continuing stream of requirements changes
• Shortfalls in externally performed tasks
• Shortfalls in externally furnished components
• Real-time performance shortfalls
• Straining computer science capabilities

• Personnel shortfalls
• Unrealistic schedules and budgets
• Developing the wrong software functions
• Developing the wrong user interface
• Gold plating
• Continuing stream of requirements changes
• Shortfalls in externally performed tasks
• Shortfalls in externally furnished components
• Real-time performance shortfalls
• Straining computer science capabilities

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The general idea of prototyping

• You depict what you think the system should look
  like.
• You test the prototypes with customers or
  (preferably) users.
• You fix up the prototypes and use what you learn
  to implement the real system.

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Waterfall kinds of processes
Requirements analysis
Prototyping
Design
Implementation
Testing
Operation
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Spiral kinds of processes
Analyze risk prototype
Draft a menu ofprogram designs
Draft a menu ofarchitecture designs
Analyze risk prototype
Draft a menu ofrequirements
Analyze risk prototype
Establishrequirements
Plan
Establisharchitecture
Plan
Establishprogram design
Implementation
Testing
Operation
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Different kinds of prototypes

• Throwaway prototypes
• Paper prototypes sketches on pieces of paper
• Low-fidelity prototypes implemented with a tool
  (e.g. Photoshop)
• Evolutionary prototypes
• High-fidelity prototypes implemented on the
  target platform not fully functional, but
  destined to be incorporated into the final
  product

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Paper prototypes

• Sketch on paper and/or post-it notes
• Dont worry (much) about colors, fonts, icons
• Doesnt need to be beautiful
• Does need to show all important UI elements
• Does need to be intelligible by users

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Example systemHere are the functional
requirements

• System will have web pages for mobile phones
  where citizens can report panhandlers
• Certain users called volunteers will view
  reports and claim panhandlers
• After visiting a claimed panhandler to offer
  social services (e.g. counseling), a volunteer
  can mark a panhandlers report as done

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Example systemHeres a panhandler report state
chart
Report status
New(just reported)
Done(visited by volunteer)
claim
unclaim
Claimed(by volunteer)
mark donesucceeds
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Testing prototypes

• Pretend to be the computer while a user tries to
  perform a use case with your prototype
• Let the user interface speak for itself
• So shut up and see if the user can do it
  himself!!!
• If the user misunderstands the user interface,
  then fix it on the spot if you can.
• Principle the user is always right (in
  prototyping)

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UC1 Report panhandler

• Actor any user
• Preconditions user views site in mobile browser
• Postconditions system records report
• Flow of events
• User selects a city
• User enters information about the panhandler
• System validates inputs
• System records report in database

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• User selects a city
• User enters information about the panhandler
• System validates inputs
• System records report in database

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UC2 Process panhandler

• Actor volunteer (member of task force)
• Preconditions volunteer logged in via mobile
  browser
• Postconditions
• Volunteer reviews list or map of panhandlers
• Volunteer marks report as claimed
• System records report as claimed
• Volunteer visits the panhandler
• Volunteer marks report as done
• System records report as done

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• Volunteer reviews list or map of panhandlers
• Volunteer marks report as claimed
• System records report as claimed
• Volunteer visits the panhandler
• Volunteer marks report as done
• System records report as done

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• Volunteer reviews list or map of panhandlers
• Volunteer marks report as claimed
• System records report as claimed
• Volunteer visits the panhandler
• Volunteer marks report as done
• System records report as done

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Some problems revealed by prototype

• What happens during validation of a panhandler
  report?
• How does the volunteer navigate from the list
  view to the map view?
• What happens if there are lots and lots of
  reports how does the user make sense of it?
• So what happens when the user marks a panhandler
  report as done?

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Non-visual problems that theprototype might not
catch

• What if there are duplicate reports?
• How do new cities get added to the system?
• Do users need to be authenticated to make a
  panhandler report? Why/why not?
• Is the mapping interface really going to run
  properly in a mobile browser? Sounds risky.
• Identifying such problems requires techniques
  beyond prototyping.

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Low-fidelity prototypes

• Fidelity faithfulness or closeness to what
  the ultimate product would look like
• Paper prototypes are ultra low fidelity
• Low-fidelity prototypes can be made in
• Photoshop
• PowerPoint
• HTML
• Any other tool thats cheap and easy to use

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Promoting health awareness with aknow your
numbers card system
http//www.flickr.com/photos/juhansonin/347137175/
sizes/o/
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Prototype splash-screen for Anaconda, an
installer framework for Linux
http//www.flickr.com/photos/sstorari/3671284171/s
izes/o/
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Prototype of what an iPod might look like with a
320x480 resolution
http//www.flickr.com/photos/ben30/2866006814/size
s/o/
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Prototype of a site for managing and sharing
photos
http//www.flickr.com/photos/
missrogue/68077527/sizes/o/
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Paper vs low-fidelity

• Low-fidelity lets you explore
• Colors, fonts, iconography, etc
• But low-fidelity
• Is more expensive
• Requires somebody with design skillz
• Is harder to fix on the fly
• And neither one can detect certain problems

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Whats next for you?

• Get organized today for HW3 due on Tuesday
• Try to meet your customer by Thursday
• Test paper prototypes
• Review your requirements definition
• Then over the weekend, update the requirements
• Remember to do your reading for Thursday.